1. The science of life is referred to as

• Options: A. anatomy B. biology C. ecology D. phylogeny

• Correct Option: B. biology

• Explanation: The word “Biology” comes from the Greek words bios (life) and logos (study). Anatomy is the study of structure, Ecology is the study of the environment, and Phylogeny is the study of evolutionary history.

2. A student dissecting an animal specimen discovered that it had two auricles and one ventricle. The animal is likely to be a/an

• Options: A. fish B. reptile C. amphibian D. bird

• Correct Option: C. amphibian

• Explanation: The heart structure is a key classifier.

  • Fish: 2 chambers (1 auricle, 1 ventricle).

  • Amphibians: 3 chambers (2 auricles, 1 ventricle).

  • Reptiles: 3 chambers (partially divided ventricle), except crocodiles (4).

  • Birds/Mammals: 4 chambers (2 auricles, 2 ventricles).

3. A change in the environment of an organism is termed

• Options: A. sensitivity B. impulse C. response D. stimulus

• Correct Option: D. stimulus

• Explanation: A stimulus is any change in the internal or external environment that provokes a reaction. Sensitivity is the ability to detect it, and response is the reaction itself.

4. The branch of biology that deals with the principles of classification of organisms is known as

• Options: A. Biological index B. nomenclature C. Taxonomy D. Ecology

• Correct Option: C. Taxonomy

• Explanation: Taxonomy is the science of naming, describing, and classifying organisms. Nomenclature is just the naming part of taxonomy.

5. The scientist who introduced binomial nomenclature in the classification of organisms was

• Options: A. Charles Darwin B. Carolus Linnaeus C. John Ray D. Louis Pasteur

• Correct Option: B. Carolus Linnaeus

• Explanation: Carolus Linnaeus acts as the “father of taxonomy” and standardized the two-name naming system (Binomial Nomenclature).

6. In the binomial system of naming organisms, the second name is called the

• Options: A. scientific name B. common name C. generic name D. specific name

• Correct Option: D. specific name (or specific epithet)

• Explanation: A scientific name consists of the Generic name (Genus) first and the Specific name (Species) second.

7. In which of the following levels of classification are the members most similar?

• Options: A. order B. Genus C. Species D. Phylum

• Correct Option: C. Species

• Explanation: The hierarchy goes Kingdom

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  Phylum

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  Class

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  Order

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  Family

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  Genus

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  Species. As you go down the list, organisms become more similar. Members of the same Species are virtually identical in structure and can interbreed.

   

8. A group of closely related organisms capable of interbreeding to produce fertile offspring are known as members of

• Options: A. kingdom B. class C. family D. species

• Correct Option: D. species

• Explanation: This is the standard biological definition of a species.

9. Organism that interbreed to produce fertile offspring belong to the same

• Options: A. class B. family C. species D. order

• Correct Option: C. species

• Explanation: Same concept as question #8.

10. Which of the following organisms is not classified as an animal?

• Options: A. Amoeba B. Paramecium C. Euglena D. Obelia

• Correct Option: C. Euglena

• Explanation: This is a tricky question based on older classification systems. Amoeba and Paramecium are Protozoa (often grouped with animals in the past, now Protists). Obelia is a Cnidarian (Kingdom Animalia). Euglena contains chloroplasts and photosynthesizes like a plant, making it the least “animal-like” among the options, as it fits into a dual classification (Plant/Animal) or Kingdom Protista.

11. Which of the following is a living organism?

• Options: A. Muscle B. Nucleus C. Yeast D. Mitochondrion

• Correct Option: C. Yeast

• Explanation: Muscle is a tissue; Nucleus and Mitochondrion are organelles (parts of a cell). Yeast is a complete, unicellular fungus (a living organism).

12. Which of the following characteristics do fungi share in common with animals?

• Options: A. Presence of digestive tract B. Movement from one place to another C. Storage of carbohydrates as glycogen D. Movement of centrioles during cell division

• Correct Option: C. Storage of carbohydrates as glycogen

• Explanation: Plants store energy as Starch. Fungi and Animals both store energy as Glycogen.

13. Which of the following pairs of structures in living organisms do not perform similar functions?

• Options: A. Lungs and spiracles B. Root hairs and mammalian hairs C. Feathers and scales D. Contractile vacuole and kidneys

• Correct Option: B. Root hairs and mammalian hairs

• Explanation:

  • Lungs/Spiracles = Breathing (Similar).

  • Feathers/Scales = Protection (Similar).

  • Contractile Vacuole/Kidneys = Osmoregulation/Excretion (Similar).

  • Root hairs absorb water/nutrients, while Mammalian hairs provide insulation/warmth. These functions are different.

14. The Arthropod in the diagram is not an insect because It

• Options: A. has a big head… B. has eight legs and no wings C. does not have visible eyes… D. has head, thorax and abdomen

• Correct Option: B. has eight legs and no wings

• Explanation: The diagram shows a Tick or Mite (Arachnid). The defining difference between Arachnids and Insects is that Insects have 6 legs and 3 body parts, while Arachnids have 8 legs and 2 body parts.

15. Which of the following statements is true about arthropods

• Options: A. Prothorax bears only legs B. Mesothorax bears only legs C. Metathorax bears only wings D. Prothorax bears only wings

• Correct Option: A. Prothorax bears only legs

• Explanation: In insects, the thorax is divided into Pro-, Meso-, and Meta-. Wings are never found on the first segment (Prothorax). The Prothorax only has a pair of legs.

16. One of the differences between plants and animals is that

• Options: A. growth is indefinite in animals… B. nutrition is autotrophic in plants… C. in plants there are excretory systems… D. plants react slowly to external stimuli while animals react more quickly.

• Correct Option: D. plants react slowly to external stimuli while animals react more quickly.

• Explanation: Plants respond via growth (tropisms) which is slow. Animals use a nervous system, which is fast. (Note: Option A is wrong because growth is indefinite in plants, not animals).

17. Which of the following organisms has both plant and animal-like features?

• Options: A. Paramecium B. Euglena C. Amoeba D. Spirogyra

• Correct Option: B. Euglena

• Explanation: Euglena has chloroplasts (plant-like) and a flagellum/gullet/eyespot (animal-like).

18. Which of the following groups embraces the rest?

• Options: A. Class B. Kingdom C. Phylum D. Species

• Correct Option: B. Kingdom

• Explanation: “Embraces the rest” means which is the largest/most inclusive category. Kingdom is the highest rank listed here.

19. The group mollusca is characterized by the presence of

• Options: A. jointed appendages B. star-shaped bodies C. backbones D. soft, non-segmented bodies

• Correct Option: D. soft, non-segmented bodies

• Explanation: Mollusks (snails, octopuses) have soft bodies, often protected by a shell. They do not have backbones or jointed legs.

20. A major difference between plants and animals is that

• Options: A. there is free movement in animals while this is limited in plants B. there is indefinite growth in animals only…

• Correct Option: A. there is free movement in animals while this is limited in plants

• Explanation: Locomotion (moving the whole body) is typical of animals. Plants are stationary (sessile).

21. A virus can sometimes be regarded as a living organism because it

• Options: A. causes disease… B. exists in a variety of shapes C. reproduces in living cells D. is easily visible…

• Correct Option: C. reproduces in living cells

• Explanation: Viruses are on the borderline of life. Their only “living” trait is the ability to replicate (reproduce), but they can only do this when hijacking a living host cell.

22. Which of the following organisms possesses both plant and animal characteristics?

• Options: A. Amoeba B. Paramecium C. Euglena D. Mucor

• Correct Option: C. Euglena

• Explanation: Repeats the concept of Question 17.

23. Which of the following characteristics is not possessed by most plants? Ability to

• Options: A. move away from stimuli B. respire C. reproduce D. adapt to environment

• Correct Option: A. move away from stimuli

• Explanation: This refers to Locomotion. Plants cannot uproot themselves and walk away from a stimulus (like fire or sun); they can only grow toward or away from it.

24. Hydra is able to perform all the following functions except

• Options: A. feeding B. movement C. photosynthesis D. egestion

• Correct Option: C. photosynthesis

• Explanation: Hydra is an animal (Phylum Coelenterata/Cnidaria). Animals cannot photosynthesize; they must eat food.

25. Euglena can be classified as an animal because of the possession of

• Options: A. nucleus B. cytoplasm C. cell wall D. pellicle

• Correct Option: D. pellicle

• Explanation: Plant cells have a rigid cell wall. Euglena lacks a cell wall and instead has a flexible protein layer called a pellicle, which allows it to change shape (an animal-like trait).

26. The following life processes are common to both plants and animals except

• Options: A. respiration B. growth C. reproduction D. photosynthesis

• Correct Option: D. photosynthesis

• Explanation: Only plants (and some protists/bacteria) perform photosynthesis. Animals do not.

27. Which of the following indicates that Euglena is a plant?

• Options: A. Conspicuous eye spot B. Presence of gullet C. Limited movement D. Presence of starch grains

• Correct Option: D. Presence of starch grains

• Explanation: Starch (or paramylum) is the storage product of photosynthesis. The ability to make and store starch is a plant characteristic.

28. Which of the following organisms exhibits both plant and animal characteristics?

• Options: A. Amoeba B. Spirogyra C. Mucor D. Euglena

• Correct Option: D. Euglena

• Explanation: A popular question! Euglena is the standard example of a bridge between plants and animals.

29. Flatworms are classified as

• Options: A. platyhelminthes B. coelenterata C. annelida D. nematoda

• Correct Option: A. platyhelminthes

• Explanation: Platy means flat, helminth means worm.

30. Species can be defined as the group of organisms that

• Options: A. resemble each other… B. are of common origin… C. resemble each other and can interbreed

• Correct Option: C. resemble each other and can interbreed

• Explanation: The biological species concept requires the ability to mate and produce fertile offspring.

31. The structure labelled I is associated with

• Options: A. sexual reproduction B. asexual reproduction C. bud Deformation D. gamete formation

• Correct Option: B. asexual reproduction

• Explanation: The diagram shows a Rhizopus fungus.

  • I points to the spores being released from the sporangium.

  • II points to the stolon (horizontal hypha).

  • III points to the rhizoids (root-like).

  • Spores are used for asexual reproduction.

32. The structure labelled II is the

• Options: A. spore B. stolon C. columella D. sporangium

• Correct Option: B. stolon

• Explanation: Structure II acts as the horizontal stem connecting the fungal growths, known as the stolon.

33. Which of the following statements about the structure labelled III is correct? It

• Options: A. secretes digestive enzymes… B. absorbs mineral salts… C. forms the root hairs… D. develops into stolon

• Correct Option: A. secretes digestive enzymes into the substrate

• Explanation: Structure III represents Rhizoids. Fungi digest food outside their bodies (extracellular digestion) by secreting enzymes through rhizoids into the food (substrate) and then absorbing the nutrients. (Option B is partially true, but A is the defining physiological mechanism of fungal nutrition).

34. The organism belongs to the Phylum

• Options: A. Rhizopoda B. Ciliophora C. Euglenophyta D. Rhodophyta

• Correct Option: C. Euglenophyta

• Explanation: The diagram is of a Euglena. It belongs to the phylum Euglenophyta.

35. Which of the following statements about living things is correct?

• Options: A. Animals respire using carbon (IV) oxide… B. Growth in plants is limited… C. Most plants respond to stimulus slowly D. Higher animals can reproduce asexually

• Correct Option: C. Most plants respond to stimulus slowly

• Explanation: As established in question 16, plant response (growth) is slow compared to animal response (movement).

36. Arrangement of the organisms in order of increasing complexity is

• Options: I-Hydra, II-Owl, III-Snake, IV-Snail

• Correct Option: C. I – IV – III – II

• Explanation:

  • I. Hydra (Cnidaria) – Simple tissue level.

  • IV. Snail (Mollusca) – Organ system level, invertebrate.

  • III. Snake (Reptile) – Vertebrate, cold-blooded.

  • II. Owl (Bird) – Vertebrate, warm-blooded (highest complexity in this list).

37. The Phylum of the organism labelled IV is

• Options: A. Coelenterata B. Platyhelminthes C. Mollusca D. Arthropoda

• Correct Option: C. Mollusca

• Explanation: Organism IV is a Snail, which belongs to the phylum Mollusca.

38. Species are groups of organisms that

• Options: A. are of different origins… B. are of common origin but cannot interbreed… C. have similar features and can interbreed freely D. resemble each other and occupy different niches

• Correct Option: C. have similar features and can interbreed freely

• Explanation: This repeats the definition of species found in questions 8, 9, and 30.

39. The Genus into which man is classified is

• Options: A. Chordata B. Mammalia C. Homo D. Sapiens

• Correct Option: C. Homo

• Explanation: The scientific name for humans is Homo sapiens.

  • Homo is the Genus.

  • sapiens is the Species.

  • Chordata is the Phylum.

  • Mammalia is the Class.